JP7370055B2 - Semiconductor device manufacturing method and wire bonding device - Google Patents

Description

The present disclosure relates to a method for manufacturing a semiconductor device and a wire bonding apparatus.

2. Description of the Related Art When manufacturing a semiconductor device, for example, in order to vertically connect semiconductor components to each other by bonding, pin wires are sometimes formed on the electrode surface of the semiconductor component, extending in a direction rising from the electrode surface. Such a pin wire can be formed, for example, by the method described in Patent Document 1. In this method, a wire is bonded to an electrode surface using a capillary, and then the capillary is moved to form a flaw in the wire using the internal edge of the capillary. Thereafter, after the portion of the wire from the joint to the scratched portion is made to stand upright from the electrode surface, the capillary is lowered to bend the wire at the scratched portion. Thereafter, by raising the capillary with the wire clamper closed, the wire is cut at the damaged area. This forms pin wires rising from the electrode surface.

Japanese Patent Application Publication No. 2007-220699

For the pin wire as described above, it is required that the height of the pin wire from the electrode surface be increased. When forming a tall pin wire by the method described in Patent Document 1, it is necessary to lengthen the wire portion from the joint to the flawed portion. However, in this method, when bending the wire at the scratched part, the capillary is lowered with the wire section standing upright from the electrode surface, so a large force is applied in the axial direction of the wire section as the capillary descends. obtain. For this reason, when the wire portion is lengthened, problems such as buckling of the wire portion due to the force are likely to occur. In this case, there will be a part that is easier to cut than the scratched part, making it difficult to reliably cut the wire at the scratched part. Therefore, with the above method, it is difficult to form a pin wire with a desired height.

The present disclosure describes a method for manufacturing a semiconductor device and a wire bonding apparatus that can easily form pin wires of a desired height.

A method for manufacturing a semiconductor device, which is an embodiment of the present disclosure, includes bonding a wire to an electrode using a capillary, and then starting from a position above the bonding portion of the wire and on the normal line of the surface of the electrode passing through the bonding portion. A first step of pulling out a predetermined length of the wire by moving the capillary while feeding out the wire to the first position, which is a shifted position; By moving the capillary while feeding out the wire, the bent portion is moved to the second position, which is a position shifted toward the joint portion from the first position when viewed from the normal direction in which the normal line extends. A second step of forming the bent portion into a wire, a third step of processing the bent portion into a portion to be cut by repeating lowering and raising of the capillary along the normal direction multiple times after forming the bent portion, and a third step of forming the bent portion into the intended cutting portion. After repeating the lowering and raising a plurality of times, in order to form a pin wire, the capillary is raised with the wire clamper closed, thereby cutting the wire at the portion to be cut.

According to the above-described manufacturing method, the wire can be reliably cut at the intended cutting portion, so a pin wire with a desired height can be easily formed.

When the capillary is moved to the second position, the bent portion may be located at a position offset from the normal line passing through the joint. In this case, it is possible to more reliably suppress the occurrence of defects such as buckling in the portion where the pin wire is to be formed, and it is possible to more reliably cut the wire at the portion to be cut.

When viewed from the normal direction, the moving distance of the capillary from the first position to the second position may be longer than the radius of the tip surface of the capillary. In this case, the wire can be cut more reliably at the portion to be cut.

When viewed from the normal direction, the distance the capillary moves from the first position to the second position may be the same as the distance the capillary moves from the junction to the first position. In this case, the wire can be cut more reliably at the portion to be cut.

When the capillary is moved to the second position, the tip end surface of the capillary may be located directly above the joint. In this case, a pin wire standing upright from the surface of the electrode can be easily obtained.

On the substrate, a plurality of semiconductor chips are stacked in a stepwise manner so that the main surface of each semiconductor chip is exposed as an exposed surface, and an electrode is provided on the exposed surface of each semiconductor chip. A pin wire may be formed for each semiconductor chip by performing the above series of steps for each semiconductor chip. The series of steps from the first step to the fourth step may be performed from the upper semiconductor chip to the lower semiconductor chip, or from the lower semiconductor chip to the upper semiconductor chip. In this case, pin wires can be easily formed for each semiconductor chip even under conditions where it is difficult to cut the wires by pressing.

A wire bonding apparatus according to another embodiment of the present disclosure includes a bonding unit including a capillary that is configured to be movable relative to an electrode, and a control unit that controls the operation of the bonding unit. After joining the wire to the electrode using the wire, the wire is fed out to a first position that is above the joint of the wire and is offset from the normal line of the surface of the electrode passing through the joint. A first control signal that causes the wire to be drawn out a predetermined length by moving the capillary; and a normal line extending from the capillary at a position above the first position after the capillary is moved to the first position. a second control signal that causes a bend to be formed in the wire by moving the capillary while feeding out the wire to a second position that is a position shifted toward the joint with respect to the first position when viewed from the direction; After the capillary is formed, the capillary is repeatedly lowered and raised along the normal direction a plurality of times, thereby generating a third control signal for processing the bending portion into the portion to be cut, and the lowering and raising of the capillary is repeated multiple times. After that, in order to form a pin wire, a fourth control signal is provided to the bonding unit to cause the wire to be cut at the portion to be cut by raising the capillary with the wire clamper closed.

According to the wire bonding apparatus described above, the wire can be reliably cut at the intended cutting portion, so that a pin wire of a desired height can be easily formed.

According to the present disclosure, a method for manufacturing a semiconductor device and a wire bonding apparatus that can easily form a pin wire of a desired height are provided.

FIG. 1 is a diagram showing the configuration of a wire bonding apparatus according to an embodiment. FIG. 2 is a diagram showing the configuration of a semiconductor device manufactured using the wire bonding apparatus shown in FIG. 1. FIG. 3 is a diagram showing the shape of the pin wire and the target point of the capillary shown in FIG. 2. FIG. 4 is a flow diagram showing steps in a method for manufacturing a semiconductor device according to an embodiment. Parts (a), (b), and (c) of FIG. 5 are diagrams showing steps in a method for manufacturing a semiconductor device according to an embodiment. Parts (a), (b), and (c) of FIG. 6 are diagrams showing steps subsequent to FIG. 5. Parts (a), (b), and (c) of FIG. 7 are diagrams showing steps subsequent to FIG. 6. FIG. 8 is a diagram showing the shape of the wire in the step (a) of FIG. 6. Parts (a) and (b) of FIG. 9 are diagrams showing steps in a method for manufacturing a semiconductor device according to a first comparative example. Parts (a), (b), and (c) of FIG. 10 are diagrams showing steps in a method for manufacturing a semiconductor device according to a second comparative example. Parts (a), (b), and (c) of FIG. 11 are diagrams showing steps subsequent to FIG. 10.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description will be omitted as appropriate.

[Wire bonding equipment]
The wire bonding device 1 shown in FIG. 1 is configured, for example, by bonding a wire 20 to an electrode provided on a semiconductor device 10 and then cutting the wire 20 to a predetermined length so that the wire bonding device 1 extends in a direction rising from the surface of the electrode. A pin wire 21 (see FIG. 3) is formed. The wire bonding apparatus 1 includes, for example, a transport unit 2, a bonding unit 3, and a control unit 4.

The transport unit 2 transports the semiconductor device 10, which is a component to be processed, to a bonding area. The bonding unit 3 includes, for example, a moving mechanism 6, a bonding tool 7, a capillary 8, and a wire clamper 9. The moving mechanism 6 moves the capillary 8 relative to the semiconductor device 10. A capillary 8 for feeding out the wire 20 is detachably provided at the tip of the bonding tool 7. The capillary 8 has a sharp cylindrical shape. A wire 20 is inserted into the capillary 8 . Capillary 8 provides heat, ultrasound or pressure to wire 20.

The wire clamper 9 is arranged above the capillary 8. The wire clamper 9 is configured to be able to grip the wire 20. When the wire clamper 9 is open, the wire 20 is not gripped by the wire clamper 9, and the wire 20 is allowed to be fed out from the capillary 8. When the wire clamper 9 is in a closed state, the wire 20 is gripped by the wire clamper 9, and feeding of the wire 20 from the capillary 8 is stopped. The wire 20 is a thin metal wire. For example, the wire 20 is made of gold (Au), silver (Ag), aluminum (Al), copper (Cu), or an alloy thereof. The diameter of the wire 20 is, for example, 20 μm (micrometers).

The control unit 4 controls the entire operation of the wire bonding apparatus 1 including the operation of the bonding unit 3. Control unit 4 provides several control signals to bonding unit 3. For example, the control signals include a signal for controlling the position of the capillary 8 with respect to the semiconductor device 10, a signal for starting and stopping the provision of heat, ultrasonic waves, or pressure, and a permission for feeding out the wire 20 from the capillary 8. and a signal for stopping. The specific control operation of the control unit 4 will be described later.

[Semiconductor device]
The semiconductor device 10 shown in FIG. 2 includes, for example, a circuit board 11, a semiconductor component 12 having a plurality of semiconductor chips 12A, 12B, 12C, and 12D, and a plurality of pin wires 21A, 21B, 21C, and 21D. . The semiconductor component 12 is fixed to the main surface 11a of the circuit board 11 by die bonding or the like, for example. The semiconductor component 12 has, for example, a structure in which a plurality of semiconductor chips 12A, 12B, 12C, and 12D are stacked in multiple stages. In one example, semiconductor component 12 is a multi-stage chip memory device.

The semiconductor chips 12A, 12B, 12C, and 12D are stacked in a staggered manner. The semiconductor chip 12A is arranged on the main surface 11a of the circuit board 11. The semiconductor chip 12B is arranged on the main surface of the semiconductor chip 12A, and is arranged so as to be offset from the semiconductor chip 12A along one direction along the main surface 11a of the circuit board 11. The semiconductor chip 12C is arranged on the main surface of the semiconductor chip 12B, and is arranged so as to be offset from the semiconductor chip 12B along the one direction. The semiconductor chip 12D is arranged on the main surface of the semiconductor chip 12C, and is arranged so as to be offset from the semiconductor chip 12C along the one direction.

A part of the main surface of the semiconductor chip 12A that is exposed from the semiconductor chip 12B is an exposed surface 12a that is exposed from the semiconductor chip 12B. A part of the main surface of the semiconductor chip 12B that is exposed from the semiconductor chip 12C is an exposed surface 12b that is exposed from the semiconductor chip 12C. A part of the main surface of the semiconductor chip 12C that is exposed from the semiconductor chip 12D is an exposed surface 12c that is exposed from the semiconductor chip 12D. The main surface of the semiconductor chip 12D is an exposed surface 12d exposed to the outer surface of the semiconductor component 12. Electrodes 31A, 31B, 31C, and 31D are provided on the exposed surfaces 12a, 12b, 12c, and 12d, respectively. The surface of electrode 31A constitutes exposed surface 12a, the surface of electrode 31B constitutes exposed surface 12b, the surface of electrode 31C constitutes exposed surface 12c, and the surface of electrode 31D constitutes exposed surface 12d.

Pin wires 21A, 21B, 21C, and 21D are provided on electrodes 31A, 31B, 31C, and 31D, respectively. Each pin wire 21A, 21B, 21C, and 21D is a part of the wire 20 cut to a predetermined length. The pin wire 21A is joined to the surface of the electrode 31A and extends in a direction rising from the surface of the electrode 31A. The pin wire 21B is joined to the surface of the electrode 31B and extends in a direction rising from the surface of the electrode 31B. The pin wire 21C is joined to the surface of the electrode 31C and extends in a direction rising from the surface of the electrode 31C. The pin wire 21D is joined to the surface of the electrode 31D and extends in a direction rising from the surface of the electrode 31D.

The upper ends of each pin wire 21A, 21B, 21C, and 21D are aligned so as to be located at the same height H with respect to the main surface 11a of the circuit board 11. Therefore, the lengths of each pin wire 21A, 21B, 21C, and 21D are different from each other. The length of the pin wire 21A provided on the lowest semiconductor chip 12A is the longest, and the length of the pin wire 21B provided on the next stage semiconductor chip 12B is shorter than the length of the pin wire 21A. The length of the provided pin wire 21C is shorter than the length of the pin wire 21B, and the length of the pin wire 21D provided on the uppermost semiconductor chip 12D is the shortest. The upper end of each pin wire 21A, 21B, 21C, and 21D is connected to an electrode of another semiconductor component (not shown) provided on the semiconductor component 12. Thereby, the semiconductor component 12 and the other semiconductor component are electrically connected to each other via the pin wires 21A, 21B, 21C, and 21D.

Hereinafter, when it is not necessary to separately explain the pin wires 21A, 21B, 21C, and 21D, they will be collectively referred to as "pin wires 21", and the electrodes 31A, 31B, 31C, and 31D will be explained separately. When there is no need to do so, these are collectively referred to as "electrodes 31."

FIG. 3 shows the shape of the pin wire 21. As shown in FIG. 3, the pin wire 21 includes a bonding portion 21a and a wire portion 21b. The bonding portion 21a is a portion that constitutes the lower end portion of the pin wire 21, and corresponds to a bonding portion 20a (joint portion) of the wire 20, which will be described later. The bonding portion 21a is physically and electrically connected to the electrode 31. The physically connected state here refers to a state in which the pin wire 21 and the electrode 31 are joined to each other. For example, the bonding portion 21a may be a portion that generates a resistance force (reaction force) against the tensile force. Further, the electrically connected state refers to a state in which the electrical resistance between the pin wire 21 and the electrode 31 is extremely small. The bonding portion 21 a is formed by pressing a spherical FAB (Free Air Ball) formed at the tip of the wire 20 against the electrode 31 by the capillary 8 . Therefore, the bonding portion 21a has a deformed hemispherical shape in which about half of the FAB is crushed.

The wire portion 21b is the main body portion of the pin wire 21, and corresponds to the wire portion 20b of the wire 20, which will be described later. The wire portion 21b extends upward from the bonding portion 21a. In this embodiment, the wire portion 21b extends along the normal direction D1 in which the normal to the surface of the electrode 31 extends. In other words, the wire portion 21b stands upright on the surface of the electrode 31. The cross section of the wire portion 21b is circular and maintains the cross-sectional shape of the wire 20. The upper end 21c of the wire portion 21b has a shape that tapers toward the upper end of the wire portion 21b. The upper end portion 21c is a cut portion of the wire 20 when the pin wire 21 is formed, and corresponds to a bent portion 20c of the wire 20, which will be described later. The height from the surface of the electrode 31 to the upper end of the pin wire 21, that is, the total length of the pin wire 21, may be, for example, 100 μm or more.

[Manufacturing method of semiconductor device]
The semiconductor device 10 described above is manufactured by the wire bonding apparatus 1. The control operation of the control unit 4 in the wire bonding apparatus 1 and the method for manufacturing the semiconductor device 10 will be described below.

First, with reference to FIG. 3, the first target point P1 to the seventh target point P7 to which the tip of the capillary 8 moves will be specifically explained. FIG. 3 shows the shape of the pin wire 21 as well as the first target point P1 to the seventh target point P7. The control unit 4 has information regarding the first target point P1 to the seventh target point P7 set in advance. The control unit 4 provides a control signal to the bonding unit 3 so that the tip of the capillary 8 sequentially moves from the first target point P1 to the seventh target point P7. Further, the control unit 4 provides the bonding unit 3 with a control signal for controlling permission and stop of feeding out the wire 20 during movement. Further, the control unit 4 provides the bonding unit 3 with a control signal for controlling permission and stop of provision of ultrasonic waves etc. from the capillary 8. Note that the tip of the capillary 8 indicates the position of the tip surface 8a of the capillary 8 (see FIG. 8). The tip surface 8a is, for example, a plane parallel to the surface of the electrode 31, and has a circular shape when viewed from the normal direction D1. Therefore, the tip of the capillary 8 may be located at the center of the tip surface 8a when viewed from the normal direction D1, for example.

Note that in the following description, a case will be exemplified in which the semiconductor component 12 is fixed and the capillary 8 is moved. However, the trajectory drawn by the first target point P1 to the seventh target point P7 may be drawn based on the relative positional relationship between the semiconductor component 12 and the capillary 8. That is, as described below, only the capillary 8 may be moved to draw a trajectory. Alternatively, both the semiconductor component 12 and the capillary 8 may be moved to draw a trajectory. For example, vertical movement may be supported by movement of the capillary 8, and horizontal movement may be supported by movement of the semiconductor component 12.

The first target point P1 indicates the position where the wire 20 is bonded to the electrode 31. In other words, the first target point P1 indicates the position where the bonding part 21a of the pin wire 21 is formed, that is, the position of the bonding part 21a. The first target point P1 is a position on the surface of the electrode 31, and may be a position at the center of the bonding portion 21a when viewed from the normal direction D1.

The second target point P2 is located directly above the first target point P1. In other words, the second target point P2 is a position on the normal line of the surface of the electrode 31 passing through the first target point P1. In the following description, the direction away from the electrode 31 along the normal to the surface of the electrode 31 will be referred to as the "upward direction," and the direction approaching the electrode 31 along the normal will be referred to as the "downward direction." Then, it can be said that the second target point P2 is a position shifted upward with respect to the first target point P1.

The third target point P3 (first position) is a position shifted from the normal line of the electrode 31 passing through the first target point P1 and the second target point P2. In other words, the third target point P3 is spaced apart from the second target point P2 by a predetermined distance along the direction in which parallel axes perpendicular to the normal to the electrode 31 extend (hereinafter referred to as "parallel axis direction D2"). set to the position. In the following description, the direction from the electrode 31A to the electrode 31B along the parallel axis direction D2 is referred to as the "right direction", and the direction from the electrode 31B to the electrode 31A along the parallel axis direction D2 is referred to as the "left direction". . Then, it can be said that the third target point P3 is a position spaced apart by a predetermined distance to the left with respect to the second target point P2. The distance from the first target point P1 to the second target point P2 and the distance from the second target point P2 to the third target point P3 are determined by the height of the pin wire 21 from the surface of the electrode 31 (total length of the pin wire 21). You can decide based on The distance from the second target point P2 to the third target point P3 may be equal to, longer, or shorter than the distance from the first target point P1 to the second target point P2.

The fourth target point P4 (second position) is a position above the third target point P3, and is on the first target point P1 side with respect to the third target point P3 when viewed from the normal direction D1. It is in a misaligned position. That is, the fourth target point P4 is a position shifted upward along the normal direction D1 with respect to the third target point P3, and the fourth target point P4 is a position shifted upward along the normal direction D1 with respect to the third target point P3, and It is set at a position shifted toward the target point P1. It can also be said that the fourth target point P4 is set at a position spaced apart from the third target point P3 by a predetermined distance in both the upper direction and the right direction. In this embodiment, the fourth target point P4 is set at a position directly above the first target point P1 and the second target point P2. In other words, the fourth target point P4 is set at a position on the normal line of the electrode 31 passing through the first target point P1 and the second target point P2. Therefore, the first target point P1, the second target point P2, and the fourth target point P4 are set on the same line. The position of the fourth target point P4 does not need to be directly above the first target point P1 and second target point P2, but is located at a position shifted from the normal line of the electrode 31 passing through the first target point P1 and second target point P2. may be set to . For example, the position of the fourth target point P4 may be a position between the third target point P3, the first target point P1, and the second target point P2 when viewed from the normal direction D1, The third target point P3 may be located further away than the first target point P1 and the second target point P2.

The fifth target point P5 is a position shifted downward from the fourth target point P4. Therefore, the fifth target point P5 is set on the same line as the first target point P1, second target point P2, and fourth target point P4 in the normal direction. In this embodiment, the fifth target point P5 is set at a position above the second target point P2. Specifically, the fifth target point P5 is set at a position between the second target point P2 and the fourth target point P4 in the normal direction D1. The fifth target point P5 may be set at a position lower than the second target point P2. For example, the fifth target point P5 may be set at a position between the first target point P1 and the second target point P2 in the normal direction D1.

The sixth target point P6 is a position shifted upward from the fourth target point P4. The seventh target point P7 is a position shifted upward from the sixth target point P6. Therefore, in the normal direction, the first target point P1, the second target point P2, the fourth target point P4, the fifth target point P5, the sixth target point P6, and the seventh target point P7 are set on the same line. be done. When the capillary 8 moves to the seventh target point P7, the wire 20 is cut, thereby forming the pin wire 21.

Next, the control operation of the control unit 4 and the method of manufacturing the semiconductor device 10 will be described with reference to FIGS. 4, 5, 6, and 7. In the following, a case will be described in which pin wires 21A, 21B, 21C, and 21D are formed in order from the bottom semiconductor chip 12A to the top semiconductor chip 12D. However, since the formation process of each pin wire 21A, 21B, 21C, and 21D is the same, here, an example in which the pin wire 21A is formed on the electrode 31A of the semiconductor chip 12A will be described as a representative example.

<First step>
The control unit 4 provides a first control signal to the bonding unit 3. The first control signal is used to move the capillary 8 to the first target point P1 (step S11), move the capillary 8 to the second target point P2 (step S12), and move the capillary 8 to the third target point P3. (step S13); an operation to cause the capillary 8 to emit ultrasonic waves for a predetermined period; and an operation to allow the wire 20 to be fed out from the capillary 8.

After receiving the first control signal, the bonding unit 3 forms a spherical FAB (see part (c) in FIG. 7) at the tip of the wire 20 fed out from the capillary 8, and then moves the capillary 8 to the first target point P1. (Step S11, see part (a) of FIG. 5). At this time, the capillary 8 presses the wire 20 against the electrode 31. Next, the bonding unit 3 emits ultrasonic waves from the capillary 8 for a predetermined period of time. As a result, the FAB of the wire 20 is deformed and bonded to the electrode 31A, forming a bonding portion 20a.

Next, the bonding unit 3 moves the capillary 8 from the first target point P1 to the second target point P2 (step S12, see part (b) of FIG. 5). Furthermore, the bonding unit 3 allows the wire 20 to be fed out from the capillary 8 by opening the wire clamper 9. That is, the bonding unit 3 moves the capillary 8 from the first target point P1 to the second target point P2 while feeding out the wire 20.

Next, the bonding unit 3 moves the capillary 8 from the second target point P2 to the third target point P3 while feeding out the wire 20 (step S13, see part (c) of FIG. 5). At this time, the wire 20 is pulled out to a predetermined length, and a wire portion 20b extending from the bonding portion 20a to the capillary 8 is formed. The wire portion 20b corresponds to the wire portion 21b, which is the main body portion of the pin wire 21, as described above. Therefore, the wire portion 20b can also be called a pin wire formation planned portion where the pin wire 21 is planned to be formed.

In steps S12 and S13, it is sufficient that the capillary 8 can be moved from the first target point P1 to the third target point P3. For example, instead of steps S12 and S13, a step of directly moving from the first target point P1 to the third target point P3 may be performed. In other words, the capillary 8 does not need to pass through the second target point P2. For example, the capillary 8 may be moved along a straight line trajectory connecting the first target point P1 and the third target point P3, or along an arcuate trajectory passing through the first target point P1 and the third target point P3. The capillary 8 may be moved.

<Second process>
Control unit 4 provides a second control signal to bonding unit 3 . The second control signal includes an operation of moving the capillary 8 to the fourth target point P4 and an operation of allowing the wire 20 to be fed out from the capillary 8 (step S14).

The bonding unit 3 that has received the second control signal moves the capillary 8 from the third target point P3 to the fourth target point P4 while feeding out the wire 20 (step S14, see part (a) of FIG. 6). At this time, the bent portion 20c is formed above the wire portion 20b, and the wire portion 20d is formed above the bent portion 20c (step S15). The bent part 20c is located between the wire part 20b and the wire part 20d, and the axial direction (extending direction) of the wire part 20d extending from the bent part 20c to the capillary 8 is connected to the wire extending from the bonding part 20a to the bent part 20c. It is changed from the axial direction (extending direction) of the portion 20b. The bent portion 20c is formed by increasing the degree of bending in the wire 20. That is, when the degree of bending in the bent portion 20c increases, the deformation of the bent portion 20c shifts from elastic deformation to plastic deformation. Then, when the bent portion 20c is plastically deformed, the bent portion 20c maintains the bent shape (arc shape) without returning to the original shape (linear shape).

In steps S14 and S15, as the capillary 8 moves from the third target point P3 to the fourth target point P4, the bent portion 20c does not stay at the third target point P3, but moves from the third target point P3 to the fourth target point P4. Move slightly to the target point P4 side. The bent portion 20c after this movement is not located on the normal line of the electrode 31 passing through the bonding portion 20a. That is, the bent portion 20c is located at a position shifted from the normal line passing through the bonding portion 20a. Therefore, the axial direction of the wire portion 20b extending from the bonding portion 20a to the bent portion 20c and the axial direction of the wire portion 20d extending from the bent portion 20c to the capillary 8 are inclined from the normal direction D1. A more specific shape of the wire 20 in steps S14 and S15 will be described later.

In step S14, the capillary 8 may be moved along a straight line trajectory connecting the third target point P3 and the fourth target point P4, or may be moved along an arcuate trajectory passing through the third target point P3 and the fourth target point P4. The capillary 8 may be moved along the line. Furthermore, in step S14, the capillary 8 does not need to be directly moved from the third target point P3 to the fourth target point P4. That is, the capillary 8 may be moved from the third target point P3 to the fourth target point P4 after passing through another target point. For example, after the capillary 8 is moved rightward from the third target point P3 to another target point, the capillary 8 may be moved upward from the other target point to the fourth target point P4.

<3rd process>
Control unit 4 provides a third control signal to bonding unit 3 . The third control signal includes an operation to stop feeding out the wire 20 from the capillary 8, an operation to move the capillary 8 to the fifth target point P5 (step S15), and an operation to move the capillary 8 to the fifth target point P5 and the sixth target point. An operation of reciprocating between point P6 (step S16) is included.

Upon receiving the third control signal, the bonding unit 3 closes the wire clamper 9 to stop feeding out the wire 20 from the capillary 8. Furthermore, the bonding unit 3 lowers the capillary 8 from the fourth target point P4 to the fifth target point P5 (step S16, see part (b) of FIG. 6). At this time, the wire portion 20b and the wire portion 20d are bent toward each other starting from the bending portion 20c. In other words, the angle between the wire portion 20b and the wire portion 20d becomes smaller, and the degree of bending of the bent portion 20c further increases. A tensile force acts on the outside (left side) of the bent portion 20c, while a compressive force acts on the inside (right side) of the bent portion 20c. As a result, a portion of the bent portion 20c is deformed so as to be crushed in a direction perpendicular to the axial direction of the bent portion 20c, and the portion becomes thinner than the other portion of the bent portion 20c. In other words, the mechanical strength of the bent portion 20c is lower than that of the other portions of the wire 20.

Next, the bonding unit 3 reciprocates the capillary 8 between the fourth target point P4 and the fifth target point P5 while stopping the feeding of the wire 20 from the capillary 8 (step S17, shown in FIG. 6). (see part (c)). That is, the capillary 8 repeatedly moves from the fifth target point P5 to the fourth target point P4 and from the fourth target point P4 to the fifth target point P5. In this way, in steps S16 and S17, the capillary 8 is lowered from the fourth target point P4 to the fifth target point P5, and the capillary 8 is raised from the fifth target point P5 to the fourth target point P4. Repeat times. By repeatedly lowering and raising the capillary 8, the wire portions 20b and 20d are bent multiple times starting from the bending portion 20c. This bending action repeatedly applies stress to the bent portion 20c.

The repeated stress causes fatigue in the bent portion 20c. This fatigue further reduces the mechanical strength of the bent portion 20c. As a result, the mechanical strength of the bent portion 20c becomes lower than the mechanical strength of the connection portion of the bonding portion 20a with the wire portion 20b. In other words, the bent portion 20c is processed into a cut portion C having lower mechanical strength than the bonding portion 20a. The scheduled cutting portion C is a portion where the wire 20 is scheduled to be cut in step S19 and step S20 (see part (b) of FIG. 7), which will be described later. In step S16 and step S17, the capillary 8 is repeatedly lowered and raised multiple times until the mechanical strength of the portion C to be cut becomes lower than the mechanical strength of the bonding portion 20a.

The mechanical strength of the connection portion of the bonding portion 20a with the wire portion 20b tends to be lower than that of other portions of the wire 20. As described above, the bonding portion 20a is formed by the capillary 8 pressing the electrode 31A on the FAB formed at the tip of the wire 20. Here, since the size of the metal crystal in the FAB changes when the FAB is joined to the electrode 31A, the size of the metal crystal differs between the FAB and the portion of the wire 20 other than the FAB. Mechanical strength tends to decrease at the boundary portion of the wire 20 where the size of the metal crystal changes. This boundary portion corresponds to the connection portion of the bonding portion 20a with the wire portion 20b. Therefore, the mechanical strength of the connection portion tends to be lower than that of other portions of the wire 20. For this reason, if the wire 20 is simply pulled upward without reducing the mechanical strength of other parts of the wire 20 other than the connection part, the wire 20 is likely to be cut at the connection part. Therefore, by making the mechanical strength of the portion C to be cut lower than the mechanical strength of the connection portion of the bonding portion 20a, the wire 20 is not cut at the connection portion, and the wire 20 is not cut at the portion C to be cut. to ensure that it is disconnected.

In this embodiment, since the capillary 8 is moved back and forth between the fourth target point P4 and the fifth target point P5, the moving distance of the capillary 8 from the fourth target point P4 to the fifth target point P5 is The moving distances of the capillary 8 from the fifth target point P5 to the fourth target point P4 are the same. However, these moving distances do not need to be the same, and may be different from each other, or may change each time the capillary 8 repeats lowering and rising. In this embodiment, the wire clamper 9 is kept closed when the capillary 8 is repeatedly lowered and raised. That is, the capillary 8 is repeatedly lowered and raised while the feeding of the wire 20 from the capillary 8 is stopped. Thereby, repeated stress can be applied efficiently to the bent portion 20c, so that the bent portion 20c can be more reliably processed into the cut portion C having lower mechanical strength than the bonding portion 20a.

<4th step>
Control unit 4 provides a fourth control signal to bonding unit 3. The fourth control signal includes an operation of moving the capillary 8 to the sixth target point P6 (step S18) and an operation of moving the capillary 8 to the seventh target point P7 (step S19).

Upon receiving the fourth control signal, the bonding unit 3 moves the capillary 8 from the fifth target point P5 to the sixth target point P6 while stopping the feeding of the wire 20 from the capillary 8 (step S18, shown in FIG. 7). (see part (a)). At this time, the wire portion 20b, the portion to be cut C, and the wire portion 20b are pulled upward in accordance with the rise of the capillary 8, and become in a state along the normal direction D1.

Next, the bonding unit 3 moves the capillary 8 from the sixth target point P6 to the seventh target point P7 while stopping the feeding of the wire 20 from the capillary 8 (step S19, part (b) of FIG. 7). reference). That is, the capillary 8 is further raised from the state shown in part (a) of FIG. At this time, the wire 20 is pulled in the axial direction (upward) as the capillary 8 rises. Here, the mechanical strength of the portion C to be cut is lower than the mechanical strength of the bonding portion 20a. In other words, the mechanical strength of the portion C to be cut is the lowest compared to other portions of the wire 20. Therefore, when the wire 20 is pulled in the axial direction, the wire 20 is cut at the cut portion C where the mechanical strength is lowest. Thereby, the pin wire 21A is formed on the electrode 31A (step S20).

Next, after forming the FAB at the tip of the wire 20, the control unit 4 moves the capillary 8 to an eighth target point P8 directly above the electrode 31B of the next-stage semiconductor chip 12B. Thereafter, the pin wire 21B is formed on the electrode 31B by performing the series of steps S11 to S20 again on the electrode 31B. Thereafter, the pin wire 21C is formed on the electrode 31C by performing the series of steps S11 to S20 again on the electrode 31C. Thereafter, the pin wire 21D is formed on the electrode 31D by performing the series of steps S11 to S20 again on the electrode 31D. Through the above steps, the semiconductor device 10 shown in FIG. 2 is obtained. The order of forming the pin wires 21 is not limited to the example described above. For example, the pin wires 21D, 21C, 21B, and 21A may be formed in the order from the top semiconductor chip 12D to the bottom semiconductor chip 12A, or the pin wires 21 may be formed in any order.

Here, with reference to FIG. 8, the shape of the wire 20 in step S14 and step S15 will be described in detail. In a state where the capillary 8 is located at the fourth target point P4, the wire 20 includes a bonding portion 20a, a wire portion 20b, a bent portion 20c, and a wire portion 20d.

The wire portion 20b is a portion of the wire 20 that continuously extends from the bonding portion 20a to the bent portion 20c. The axial direction D3 of the wire portion 20b is inclined with respect to the normal direction D1 and the parallel axis direction D2. That is, the axial direction D3 of the wire portion 20b includes a component in the normal direction D1 and a component in the parallel axis direction D2. The angle θ1 between the axial direction D3 and the normal direction D1 of the wire portion 20b is within a range larger than 0° and smaller than 90°. In other words, the angle θ1 is an acute angle. The angle θ1 may be, for example, within a range of 15° or more and 65° or less, preferably within a range of 25° or more and 40° or less. The angle θ2 between the axial direction D3 and the parallel axis direction D2 of the wire portion 20b is also within a range of greater than 0° and smaller than 90°. The angle θ2 may be, for example, within a range of 25° or more and 75° or less, preferably within a range of 25° or more and 40° or less. The angle θ2 may be different from the angle θ1 or may be the same as the angle θ1.

The wire portion 20d is a portion of the wire 20 that continuously extends from the bent portion 20c to the capillary 8. The axial direction D4 of the wire portion 20d is inclined with respect to the normal direction D1 and the parallel axis direction D2. That is, the axial direction D4 of the wire portion 20d includes a component in the normal direction D1 and a component in the parallel axis direction D2. The angle θ3 between the axial direction D4 and the normal direction D1 of the wire portion 20d is within a range larger than 0° and smaller than 90°. The angle θ3 may be, for example, within a range of 15° or more and 65° or less, preferably within a range of 25° or more and 40° or less. The angle θ4 formed between the axial direction D4 and the parallel axis direction D2 of the wire portion 20d is also within a range larger than 0° and smaller than 90°. The angle θ4 may be, for example, within a range of 25° or more and 75° or less, preferably within a range of 25° or more and 40° or less. The angle θ4 may be different from the angle θ3 or may be the same as the angle θ3.

The axial direction D4 of the wire portion 20d intersects the axial direction D3 of the wire portion 20b. That is, the axial direction D4 of the wire portion 20d is different from the axial direction D3 of the wire portion 20b. The angle θ5 formed by the axial direction D4 of the wire portion 20d and the axial direction D3 of the wire portion 20b is represented by the sum of the angle θ2 and the angle θ4. The angle θ5 is within a range greater than 0° and less than 180°. The angle θ5 may be, for example, within a range of 50° or more and 150° or less, preferably within a range of 50° or more and 80° or less.

In this embodiment, the angle θ1 is the same as the angle θ3, and the angle θ2 is the same as the angle θ4. That is, the shape of the wire portion 20d is symmetrical to the shape of the wire portion 20b with respect to the parallel axis passing through the center of the bent portion 20c. Therefore, the length of the wire portion 20b in the axial direction D3 is the same as the length of the wire portion 20d in the axial direction D4. In this case, the length L1 from the parallel axis passing through the vertical center of the bent portion 20c to the surface of the electrode 31A is the same as the length L2 from the parallel axis to the tip surface 8a of the capillary 8. That is, the ratio (L1/L2) between length L1 and length L2 is 1 (that is, L1:L2=1:1). As an example, each of the length L1 and the length L2 is 300 μm. The length L1 and the length L2 do not need to be the same and may be different from each other. The ratio of length L1 to length L2 (L1/L2) may be in the range of 0.5 or more and 2.0 or less, and preferably in the range of 0.7 or more and 1.5 or less. It may be within. Each of the lengths L1 and L2 may be, for example, in the range of 200 μm or more and 400 μm or more, or preferably in the range of 250 μm or more and 350 μm or more.

The length of the wire portion 20b in the axial direction D3 corresponds to the distance from the first target point P1 to the third target point P3. In other words, the length of the wire portion 20b in the axial direction D3 is determined by the moving distance d1 of the capillary 8 along the normal direction D1 from the first target point P1 to the third target point P3, and the length of the wire portion 20b in the axial direction D3. It is determined based on the moving distance d2 of the capillary 8 along the parallel axis direction D2 to the target point P3. The moving distance d1 can also be said to be the moving distance of the capillary 8 from the first target point P1 to the third target point P3 when viewed from the parallel axis direction D2. The moving distance d2 can also be said to be the moving distance of the capillary 8 from the first target point P1 to the third target point P3 when viewed from the normal direction D1.

The length of the wire portion 20d in the axial direction D4 corresponds to the distance from the third target point P3 to the fourth target point P4. In other words, the length of the wire portion 20d in the axial direction D4 is the moving distance d3 of the capillary 8 along the normal direction D1 from the third target point P3 to the fourth target point P4, and It is determined based on the movement distance d4 of the capillary 8 along the parallel axis direction D2 to the target point P4. The moving distance d3 can also be said to be the moving distance of the capillary 8 from the third target point P3 to the fourth target point P4 when viewed from the parallel axis direction D2. The moving distance d4 can also be said to be the moving distance of the capillary 8 from the third target point P3 to the fourth target point P4 when viewed from the normal direction D1.

In this embodiment, the moving distance d2 and the moving distance d4 are the same, and each of the moving distance d2 and the moving distance d4 is longer than the radius R of the tip surface 8a of the capillary 8. The radius R of the tip surface 8a is, for example, 20 μm. Further, the moving distance d3 is slightly longer than the moving distance d1. As described above, when the capillary 8 is moved from the third target point P3 to the fourth target point P4, the bent portion 20c is slightly shifted from the third target point P3 toward the fourth target point P4. In consideration of the amount of deviation of the bent portion 20c upward from the third target point P3 at this time, the moving distance d3 is set longer than the moving distance d1. The moving distance d3 may be the same as the moving distance d1 or may be shorter. The moving distance d2 does not have to be the same as the moving distance d4, and may be longer or shorter than the moving distance d4. The moving distance d2 may be longer than the moving distance d1. In this case, the angle θ2 can be made small. In other words, the degree of bending in the bent portion 20c can be increased. This makes it possible to easily form the bent portion 20c.

When the capillary 8 is located at the fourth target point P4, the tip surface 8a of the capillary 8 is located directly above the bonding portion 20a. The state in which the distal end surface 8a is located directly above the bonding part 20a is the state in which the entire bonding part 20a is contained within the distal end surface 8a when viewed from the normal direction D1, that is, the state in which the distal end surface 8a is located directly above the bonding part 20a. This refers to a state in which all the normal lines of the electrode 31 pass through the inside of the tip surface 8a. In this embodiment, the position of the capillary 8 is set such that the central axis CL of the tip surface 8a passes through the center of the bonding portion 20a when viewed from the normal direction D1. The central axis CL of the distal end surface 8a may be deviated from the center of the bonding portion 20a as long as it is located directly above the bonding portion 20a.

The effects of the method of manufacturing the semiconductor device 10 and the wire bonding apparatus 1 according to the present embodiment described above will be explained together with the problems of the comparative example.

FIG. 9 shows steps in a method for manufacturing a semiconductor device according to a first comparative example. This manufacturing method differs from the manufacturing method of the semiconductor device 10 according to the present embodiment in that a bent portion is not formed in the wire. In the manufacturing method according to the first comparative example, first, the bonding part 120a is formed by bonding the wire 120 to the electrode 131 of the semiconductor component 112 using the capillary 108, and then the capillary 108 is raised while feeding out the wire 120. As a result, a wire portion 120b extending upward from the bonding portion 120a is formed (see part (a) of FIG. 9). Next, by raising the capillary 108 with the wire clamper closed, the wire 120 is cut (see part (b) of FIG. 9). Here, as described above, since the connecting portion between the bonding portion 120a and the wire portion 120b is a portion where the size of the metal crystal changes, the mechanical strength of the connecting portion is higher than that of the other portions of the wire 120. Low compared to mechanical strength. Therefore, if the capillary 108 is simply raised in this state, the wire 120 will be cut at the connection portion, as shown in part (b) of FIG. Therefore, in the method for manufacturing a semiconductor device according to the first comparative example, it is difficult to form a pin wire extending in a direction rising from the electrode 131.

FIG. 10 shows steps in a method for manufacturing a semiconductor device according to a second comparative example. FIG. 11 shows a step subsequent to the step shown in FIG. This manufacturing method is common to the manufacturing method according to the present embodiment in that a bent portion (scarred portion) is formed in the wire. However, this manufacturing method differs from the manufacturing method according to the present embodiment in that the wire is bent while standing upright from the electrode. In the manufacturing method according to the second comparative example, first, the bonding part 120a is formed by bonding the wire 120 to the electrode 131 of the semiconductor component 112 using the capillary 108, and then the capillary 108 is raised while paying out the wire 120. As a result, a wire portion 120b extending upward from the bonding portion 120a is formed (see part (a) of FIG. 10). Next, the capillary 108 is moved leftward and then lowered (see part (b) of FIG. 10). At this time, a scratched portion 120c is formed in the wire 120 by the inner edge of the tip of the capillary 108 (see part (c) of FIG. 10). Then, after raising the capillary 108 while letting out the wire 120, the capillary 108 is moved to the right. At this time, the wire portion 120b is in a state along the normal direction of the surface of the electrode 131. In other words, the wire portion 120b stands upright from the surface of the electrode 131.

Next, by lowering the capillary 108, the wire 120 is bent at the damaged portion 120c (see part (a) of FIG. 11). That is, the wire portion 120d is bent toward the wire portion 120b using the scratched portion 120c as a starting point. At this time, the axial direction of the wire portion 120b is along the normal direction of the surface of the electrode 131. That is, the axial direction of the wire portion 120b is the same direction as the descending direction of the capillary 108 (that is, the pressing direction of the capillary 108), which descends along the normal direction. In this case, the axial force of the wire portion 120b generated in response to the pressing force of the capillary 108 increases. When the axial force of the wire portion 120b increases, buckling tends to occur in the wire portion 120b (see part (b) of FIG. 11). When buckling occurs in the wire portion 120b, a bent portion 120e is formed in the wire portion 120b due to the buckling. At this time, stress acts on the bent portion 120e as the capillary 108 descends, and the mechanical strength of the bent portion 120e decreases due to the stress. In this state, if the wire clamper is closed and the capillary 108 is raised, the wire 120 may be cut at the bent portion 120e instead of the damaged portion 120c (see part (c) of FIG. 11). In other words, there is a possibility that the wire 120 cannot be cut at the target position (scarred portion 120c). In this case, the pin wire 121 is formed at a height lower than the intended height. Therefore, in the method for manufacturing a semiconductor device according to the second comparative example, it is difficult to form pin wires with a desired height.

In the manufacturing method of the semiconductor device 10 and the wire bonding apparatus 1 according to the present embodiment, when forming the bent portion 20c in the wire 20, the capillary 8 is moved to the fourth target point P4 after passing through the third target point P3. ing. Thereby, when the capillary 8 is moved to the fourth target point P4, the axial direction D3 of the wire portion 20b can be tilted from the normal direction D1. In this case, since the axial direction D3 of the wire portion 20b and the pressing direction by the capillary 8 (that is, the normal direction D1 in which the capillary 8 descends) are different, the wire portion 20b may buckle when the capillary 8 is lowered. Problems are less likely to occur. In other words, in a state where the axial direction D3 of the wire portion 20b is different from the direction in which the capillary 8 presses, the axial force of the wire portion 20b generated in response to the pressing force of the capillary 8 becomes smaller, so buckling is less likely to occur in the wire portion 20b. Become. If such defects such as buckling are suppressed, a situation in which the wire 20 is cut at a portion other than the intended cutting portion C when the capillary 8 is raised is suppressed. As a result, the wire 20 can be reliably cut at the cut portion C, so the pin wire 21 of a desired height can be easily formed.

Furthermore, in the manufacturing method of the semiconductor device 10 and the wire bonding apparatus 1 according to the present embodiment, unlike the case where the wire 20 is cut by pressing the wire 20 against the surrounding pressing part, the capillary 8 is cut in the air. The wire 20 is cut by repeated lowering and raising operations. In other words, the wire 20 is cut only by the movement of the capillary 8 in the air without pressing the wire 20 against the pressing portion. When pressing the wire against the pressing portion, a capillary presses the wire against the pressing portion to form a thin wall portion in the wire. Since the mechanical strength of this thin portion is lower than that of other portions of the wire, the wire can be cut at the thin portion by raising the capillary after forming the thin portion. When performing such a pressing operation, it is necessary to secure a pressing portion having a relatively large area around the bonded portion of the wire in order to press the wire. However, if the positions where the pressing portion can be secured are limited, it may be difficult to perform the pressing operation. For example, if the distance between the wire joint and the pressing part becomes a certain distance, the parts installed between the wire joint and the pressing part will become an obstacle, and the pressing operation from the joint to the pressing part will be hindered. You may become unable to do so. Furthermore, if the position of the pressing part is limited, the position of the thin wall portion formed in the pressing part is also limited, making it difficult to form a pin wire of a desired height. On the other hand, in the method for manufacturing the semiconductor device 10 and the wire bonding apparatus 1 according to the present embodiment, as described above, the wire 20 can be cut only by the operation of the capillary 8 in the air. Even in situations where it is difficult to press the wire 20 against the pin wire 21, the pin wire 21 can be easily formed to have a desired height.

In this embodiment, when the capillary 8 is moved to the fourth target point P4, the bent portion 20c is located at a position offset from the normal line of the electrode 31 passing through the bonding portion 20a. In this case, when the capillary 8 is moved to the fourth target point P4, the state in which the axial direction D3 of the wire portion 20b is inclined from the normal direction D1 can be maintained more reliably. In other words, the state in which the axial direction D3 of the wire portion 20b and the pressing direction by the capillary 8 are different can be maintained more reliably. As a result, it is possible to more reliably suppress the occurrence of defects such as buckling in the wire portion 20b, and it is possible to more reliably cut the wire 20 at the portion C to be cut.

In this embodiment, the moving distance of the capillary 8 from the third target point P3 to the fourth target point P4 is longer than the radius of the tip surface 8a of the capillary 8 when viewed from the normal direction D1. In this case, it is possible to prevent the length of the wire portion 20d from the capillary 8 to the bent portion 20c from becoming extremely short. Thereby, it is possible to suppress a situation in which the repeated stress generated in the bent portion 20c becomes extremely small. As a result, the bent portion 20c can be more reliably processed into the cut portion C having lower mechanical strength than the bonding portion 20a, so the wire 20 can be cut at the cut portion C more reliably.

In this embodiment, when viewed from the normal direction D1, the movement distance of the capillary 8 from the third target point P3 to the fourth target point P4 is the movement distance of the capillary 8 from the bonding part 20a to the third target point P3. It is the same as distance. In this case, the length of the wire portion 20d from the capillary 8 to the bent portion 20c can be made the same as the length of the wire portion 20b from the bonding portion 20a to the bent portion 20c. Thereby, it is possible to suppress a situation in which the repetitive stress generated in the bent portion 20c becomes small. As a result, it is possible to more reliably process the bent portion 20c into the intended cutting portion C, which has lower mechanical strength than the bonding portion 20a, so that the wire 20 can be more reliably cut at the intended cutting portion C. can.

In this embodiment, when the capillary 8 is moved to the fourth target point P4, the capillary 8 is located directly above the bonding portion 20a. In this case, the wire portion 20b can be placed upright on the surface of the electrode 31. By closing the wire clamper 9 and raising the capillary 8 in this state, the pin wire 21 standing upright from the surface of the electrode 31 can be easily obtained.

In this embodiment, by performing a series of steps from step S11 to step S20 for each of the semiconductor chips 12A, 12B, 12C, and 12D of the semiconductor component 12, the pin wires 21 are attached to each of the semiconductor chips 12A, 12B, 12C, and 12D. is formed. Further, a series of steps from step S11 to step S20 are performed in order from the bottom semiconductor chip 12A to the top semiconductor chip 12D. In the semiconductor component 12, if a method is used in which the wire 20 is cut by the pressing operation of the capillary 8 that presses the wire 20 against the surrounding pressing portion, the main surface 11a of the circuit board 11 having a relatively large area may be used as the pressing portion. It is possible to use it. However, in this method, when trying to form pin wires 21B on the semiconductor chip 12B located above it after forming the pin wires 21A on the semiconductor chip 12A, the movement of the capillary 8 from the semiconductor chip 12B to the main surface 11a of the circuit board 11 is difficult. , the wire 20 may not be able to be cut by the pressing operation of the capillary 8 because it is obstructed by the pin wire 21A formed on the semiconductor chip 12A in the middle. On the other hand, according to the manufacturing method of the semiconductor device 10 and the wire bonding apparatus 1 according to the present embodiment, the wire 20 can be cut only by the movement of the capillary 8 in the air without performing such a pressing operation. Therefore, the pin wires 21 can be easily formed for each of the semiconductor chips 12A, 12B, 12C, and 12D even under a situation where it is difficult to cut the wires 20 by pressing operation.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments and may be implemented in various forms.

DESCRIPTION OF SYMBOLS 1... Wire bonding device, 3... Bonding unit, 4... Control unit, 8... Capillary, 8a... Tip surface, 9... Wire clamper, 10... Semiconductor device, 11a... Main surface, 12... Semiconductor component, 12A, 12B, 12C , 12D...Semiconductor chip, 12a, 12b, 12c, 12d...Exposed surface, 20...Wire, 20a...Bonding part (joint part), 20b...Wire part, 20c...Bending part, 21, 21A, 21B, 21C, 21D... Pin wire, 31, 31A, 31B, 31C, 31D...electrode, C...cutting area, D1...normal direction, d2, d4...movement distance, P3...third target point (first position), P4...fourth target Point (second position), R...radius.

Claims (8)

After bonding the wire to the electrode using a capillary, the wire is placed at a first position above the bonded portion of the wire and deviated from the normal line of the surface of the electrode passing through the bonded portion. a first step of drawing out the wire to a predetermined length by moving the capillary while drawing out the wire;
After the capillary is moved to the first position, the capillary is located at a position above the first position, and is shifted toward the joint part side with respect to the first position when viewed from the normal direction in which the normal line extends. a second step of forming a bent portion in the wire by moving the capillary while feeding out the wire to a second position, which is the second position;
After forming the bent portion, a third step of processing the bent portion into a portion to be cut by repeating lowering and raising of the capillary along the normal direction a plurality of times;
After repeating the lowering and raising of the capillary a plurality of times, in order to form a pin wire, a fourth step of raising the capillary with a wire clamper closed to cut the wire at the portion to be cut; A method for manufacturing a semiconductor device comprising: 2. The method for manufacturing a semiconductor device according to claim 1, wherein when the capillary is moved to the second position, the bent portion is located at a position offset from the normal line passing through the joint portion. 3. The semiconductor device according to claim 1, wherein a moving distance of the capillary from the first position to the second position is longer than a radius of a tip surface of the capillary when viewed from the normal direction. Production method. When viewed from the normal direction, a moving distance of the capillary from the first position to the second position is the same as a moving distance of the capillary from the joint to the first position. 4. A method for manufacturing a semiconductor device according to any one of 1 to 3. 5. The method of manufacturing a semiconductor device according to claim 1, wherein when the capillary is moved to the second position, the tip end surface of the capillary is located directly above the bonding portion. A plurality of semiconductor chips are stacked on the substrate in a stepwise manner such that the main surface of each semiconductor chip is exposed as an exposed surface,
The electrode is provided on the exposed surface of each semiconductor chip,
6. The semiconductor device according to claim 1, wherein the pin wire is formed for each semiconductor chip by performing a series of steps from the first step to the fourth step for each semiconductor chip. manufacturing method. 6. A series of steps from the first step to the fourth step are performed in the order from the semiconductor chip in the upper stage to the semiconductor chip in the lower stage, or in the order from the semiconductor chip in the lower stage to the semiconductor chip in the upper stage. A method for manufacturing a semiconductor device according to . a bonding unit including a capillary configured to be movable relative to the electrode;
A control unit that controls the operation of the bonding unit,
The control unit includes:
After a wire is bonded to the electrode using the capillary, a first position is a position above the bonding portion of the wire and is deviated from the normal line of the surface of the electrode passing through the bonding portion. a first control signal that causes the wire to be pulled out a predetermined length by moving the capillary while letting out the wire;
After the capillary is moved to the first position, the capillary is located at a position above the first position, and is shifted toward the joint part side with respect to the first position when viewed from the normal direction in which the normal line extends. a second control signal that causes the wire to form a bent portion by moving the capillary to a second position where the wire is fed out;
a third control signal for processing the bent portion into a portion to be cut by repeating lowering and raising of the capillary along the normal direction a plurality of times after forming the bent portion;
A fourth control signal that causes the wire to be cut at the intended cutting portion by raising the capillary with the wire clamper closed to form a pin wire after repeating the lowering and raising of the capillary a plurality of times. A wire bonding apparatus that provides the bonding unit with the following.

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